Glass composition



UNITED vsrares PATENT OFFICE.

HARRY T. BELLAMY, 01 OAK PARK, AND BURTON Tl SWEELY, OF (HOW; ILLINOIS,

ASSIGNORS TO WESTERN ELECTRIC COMPANY, INCORPORATED, 013 NEW YORK,

N. Y., A CORPORATION OF NEW YORK.

GLASS COMPOSITION.

Specification of Letters Patent. t nt May 16 1922 No Drawing. Originalapplication filed November, 16, 1918, Serial No. 262,852. Divided andthis application filed March 20, 1920. Serial No. 367,395.

To all whom it may concern:

Be it known that we, HARRY T. VBELLAMY and BURTON T. SwnnLY, citizens ofthe United States, residing at Oak Park, in the county of Cook and Stateof Illinois and at Ciceroin the county of Cook and ltate of Illinois,respectively, have invented certain new and useful Improvements in GlassCompositions, of which the following is a full, clear, concise, andexact description.

This invention relates to gram compositions, and more particularly toglass compositions which are articularly adapted for use as binders inbig resistance compounds. In all artificially compounded porcelains andsimilar silicates as well as the natural occurring silicates such asclays, etc, which are used at the present time as insulators inelectrical heating element-s, a sharp decrease in resistance occurs withincrease in temperature within certain limits. This is due to the factthat certain substances have the peculiar property of conductingelectricity and acting aselectrolytes when a silicate body containinthem is raised in temperature, the activity being more pronounced uponincreasing either the temperature or' amount of electrolyte present.

- It has been found that, by oombining certain elements such as talc,silica sand, and I ball clay with a. suitable binder, a compound can beproduced which will have a high resistance at high temperatures onaccount ofbeing practically free from electrolytic action, and will becapable of being readily formed or Worked into any desired shape. Such acompound is described and claimed in an allowed application of theseinventors,

Serial No. 262,852, filed November 16, 1918, of which. this applicationis a division.

It is the purpose of this invention to proishe'd body do not becomeelectrolytically active at the temperatures at which a resistanceelement of time class 1s worked. These substances are the silicates and.borates of calcium and barium in combination with alumina. The amountsof theseseveral substances which produce a binder which satisfactorilymeets the requirements are The glass above described when combined withhighly refractory materials, such as the powdered talc, quartz sand, andclay entering into the composition of the resistance element, acts in anentirely different manner from. that of the usual fluxes in artificiallycompounded silicates. The resulting degree of hardness andstrength of the finwhen the usual fiux'es such as feldspar, whitin etc,are used, is directly proportional to t e temperature at which theeutectic mixture between the various components forms, the length oftime necessary to form sufiicient of these eutectic mixtures to bond thebody, and the length of time over which the body is subjected to heattreatment. In the case of the glass binder of this invention theeutectic relation has practically no effect, and if sufiicient heattreatment to melt the glass is accorded, the rlesultant body will be ashard and strong as t e duce a glass binder having non-electrolytictogether the different refractory components Y characteristics and whichmay be readily used with the other elements constituting the body oftheresistance to produce a-workable and permanent article.

In accordance wlth this invention, the

glass binder .is composed of substances which of the body and does notdepend upon partial fusion of these components to create the bond.

' What is claimed is;

v 1'. A binder for high resistance compositions, comprising anon-electrolytic glass glass since it fuses around and cements composedof silicates and borates of calcium per cent clay, fifty-two per centboric acid,

and barium. and fourteen per cent quartz. 10 2. A batch fornon-electrolitic glass, com- In witness whereof, We hereunto subscribeprising Whiting, barium carbonate, clay, our names this first day ofMarch, A. D. 5 boric acid, and quartz. 1920.

3. A batch for non-electrolytic glass, comprising approximately ten percent Whiting, HARRY T. BELLAMY.

twenty-one per cent barium carbonate, three BURTON T. SWEELY.

